1. Field of the Invention
The present invention relates to a contents retrieval system for performing a retrieval of contents on a communication network, and a contents retrieval program storage medium.
2. Description of the Related Art
As technology of a communication network advances, user needs for retrieving contents on the communication network is being increased. In the field of the contents retrieval system, there is widely provided a retrieval service in which a server at a client side, who receives a retrieval request from a user, retrieves contents on the communication network and provides a retrieval result for the user.
As such a type of retrieval service system, for example, Japanese Patent Laid Open Gazette Hei. 11-15766 discloses an information exchange apparatus comprising a server for providing an application service such as various types of application software, a client receiving an offer of the application service from the server, communication networks each for connecting the server with the client, and communication network connecting means for mutually connecting the communication networks to each other.
However, according to the former retrieval service system, in the event that a client requests of a server a retrieval service, there is a need for the client to maintain a connection state with the server until the client receives the retrieval result from the server.
For example, in the event that a content of the retrieval is contents of image data on a communication network, it often happens that a considerable long time is required for the retrieval. Maintaining a connection state of the communication network for such a long time makes the cost for communication run up, and brings about the possibility that another communication is hindered because a communication line between the client and the server is blocked.